Attachment for wireless receivers



w. M. BRUCTQE ATTACHMENT FOR WIRELESS RECEIVERS Jan. 6, 1931.

Filed June 22, 1927 JNVENTOR.

I I BY I M ATTORNEYS.

w z I um I Patented Jan. 6, 1931 i UNITED STATES PATENT OFF'ITCE WI LIAM H. BRUCE, or sranmrmnn, onro arrscnmnn'r r03 wrannnss ancmvans Application filed June 22, 1927. Serial No. 200,698".

M invcntionrelates to an attachment for with four openings of difierent diameters to wire ess receivers and has for its object to. geceive the well known tube terminals 1, 2, V provide means for tuning the plate circuit and a. This plate or disk 01 will be Profof any desired thermionic tube of a receiverably constructed ofsubstantiall the same ing set in which provision is "not made for size or diameter and shape as the ase of the 56 such tuning. tube bso that when slipped into place over In its preferred form it consists of a tunthe tube terminals 1 2, 3 and 4 it will form ing device and a connector which can be a slight extension of the tube base. inserted between a thermionic tube and its The plate 01 is provided on one side with v socket in such a manner; that the tuning detwo contacting devices 02 and as. The one 60 vice will be looped in. the plate circu t of 02 is provided at its lower end with alateralsaid tube while the other circuits such as 1y projecti'nfi part 04 which projects across the filament and grid will be unchanged. the end of t e tube terminal 2, which is the In the accompanying drawings in which terminal for the plate circuit, and it is prolike parts are represented by similar letters vided on one side with an insulated strip 05 of reference: which lies across the tube2with the other side Fig. 1 is a diagrammatic view illustratof the projection 04 of conducting material ing my invention and showingthe c rcuits o d,

embodying my improved tunmg devl The other contacting device 03 is preferably Fig. 2 1s a p rspe iv i w 9 a in the nature of flexible metallic strips whic onic tube and its socket to which the conwhenconnected d bl di place t, th v neotor is attached. I v bottom of the tube will contact on a side or Fig. 3 is a perspective view of the tube id f th l t t i l 2 and connector removed from the socket. From-the contacts 02 and 03 are terminals Fig. 4 and Fig. 5 ar detall Views of the 06 and 07 which extend from these contacts 7 connector. c2 and 03 to a point above the socket 121 when l 6 5 a Sectlonal ng a the tube is in place and preferably above the 'e 1 base portion of he tube 6 particularly-if the In th d a represents the same is made of metal. These terminals 06 30. receiving socket of a three element thermld 7 are d f hi strips f t l h so 01110 tube 6; 0 1S COIlIlCQtOI to be 'as copper and Preferably fer a dis. e e between the tllbe Socket t Ph tance suflicient to pass beyond the base of the thermlqmc 9. 2. 1s a ,sllltable n g tube "when the connector is'in place and this mechamsm whlch 1s connected to the terrmmay accom li h d b enameling th t 35. nals of the connector 0 so that when the parts n f the stnps r in any other d i d F in P as ilhlstml'ied in the sqeml With the connector in place on the tube it 6 tupmg devlce W111 be P d. 1n the will be inserted in the socket in the usual way P 'F 9f P b s r t w y as the different sizes of tube terminals securing" S w dwgmmmetwally The the proper relative position of the parts to intuning device wh1ch y be of l sure the desired connection. The terminals 1, 1 known form elthel h nature Q 3 and4will contact with the socket terminals b inductancs Vamable capacltles IS in the usual way. The-terminal 2, however,

Preferably enclosed in a separate casing 115 for the plate circuit by'reason ofthe projectindicated by dotted lines in Fig. land conin ti bf ghev nt t 2 ill t ke nected by suitable "flexible connections or contact with its socket terminal, but the concord to the terminals'of the connector. tact'e2'will make connection with said ter- The preferred formof theconnectoras minal andinasmu h as the terminal2-is i-n f illustratedinlfjgs. 3, 4i8nd 5 consists of a electrical connection with the contact 03. it plate or disk 01 of thin insulating material willbe seen that the terminal c6-is electrically such as hard rubber or-fibre and it is pierced connected to the socket terminal of-the plate circuit and-the terminal 06 is electrically connected to the tube terminal of the plate.

To complete the circuit the tuning device (1 by means of. suitable electrical connection preferably in the form of flexible cords is attached as indicated in Fig. 1 to the terminals 06 and 07- so that the tuning device (13 is looped into the plate circuit and furnishes means for tuning the plate circuit of any tube to which the connector-may be applied.

Fig. 6 shows a modified form of connector in which an auxiliary socket 08 is provided preferably of insulating material. This auxiliary socket has four terminals, only two, 5 and 6, being shown in; this drawing. All of these terminals on the auxiliary socket with the exception of that corresponding to the tube terminal 2 will be provided with contacts 09 which engage the tube terminals and establishes a connection between said tube terminal (when it is in place) and the auxiliary socket terminal. The socket terminal 5 corresponding to the tube terminal 2 is connected to a lead 010 which extends to the outside of the auxiliary socket .and a. contact 011 on the interior oflthe auxiliary socket by a lead 012 which extends to the outside of the auxiliary socket andthi s contact 011 is adapted to make electrical connection with the plate terminal 2 when the tub'eis in place. It will be under stood that the leads from the tuning device (Z will in this case be continuations of leads 010 and 012.

In establishing the connection with this form of connector a tube is removed and the auxiliary socket is placed into the regular tube socket after which the tube is inserted in the connector socket the upper plate 013 successfully consists of a coil d, a contact d2 pivoted at d3 and provided with a handle d4 and a pointer or index hand d5 moving over a graduated scale d6. When in the zero s1- tion this tuning device will have no a ecton the incoming signals, but as the hand d4 is moved along the scale a greater or less number of turns of the coil (11 are included in the plate circuit, thus tuning the plate circuit to the incoming si nals.

Having thus' descri ed my claim: f

A connector for thermionic tubes embodying a disk of insulating material whose outer periphery is approximately coextensive with the base of the tube and having perforations to receive the legs of the tube, a contacting device adjacent one of the perforations and adapted to engage with the tube leg which projects therethrough and a separate contacting device connected to the under side of the disk and having an ofiset portion which projects in line with the axis of the opening through which the leg extends and below the contacting device adapted to engage said leg, said offset contacting device being insulated on its upper side to prevent electrical contacts with the projecting tube leg and two invention, I

independent thin metallic strips connected to the respective contacting devices and around the periphery of the disk and adapted to project upwardly along the base of the tube and between said base and the tube socket, said metallic strips being insulated.

In testimony whereof, I have hereunto set my hand this 2nd day of March, 1927.

WILLIAM M. BRUCE.

of said auxiliary socket being provided with 1 perforations to receive the usual tube terminals; the tuning device will be looped into the plate circuitof the tube by means of'the contact 011 engaging the tube terminals 2 and the lead 010 which extends to the auxillary socket terminal 5.

This device is applicable to any of the usual receiving sets (except the so-called superheterodyne circuit) in which no provision is made for tuningthe late circuit and when so applied the ampli cation of the set may e increased many fold particularly when distant stations or low-powered stations are being received and from which the signals are with difiiculty beingobtained.

The tuning device plate circuit of any tector or of radio may be connected to the of the tubes, either deamplification and will amplify signals received on the set very materially and if the tuning device is applied to the detector tube or a tube forming the I second or third stage of amplification the danger of disturbances from tube squeals caused by the oscillations of the tube in tuning the plate circuit will be obviated.

A simple form of tuning which I have used 

